For many crops, modern agricultural practice embraces growing row crops in a furrowed field with the row crop being planted on the top of ridges in rows where each row is separated from an adjacent row by a furrow. In many cases, the depth between the trough of the furrow and the apex of the ridge can be six to eight inches high. In this way, agricultural implements can travel in the furrows without compacting the soil adjacent the root structure of the plants growing on the ridges. In addition, for purposes of irrigation, plants which prefer an environment where their root structure does not have to stand in water mandate the use of the furrow and ridge arrangement. Water standing in the furrows does not adversely effect the fibrous root structure.
Vehicle widths, measured as the space between facing tires on opposite sides of the trailer, is about eighty inches. The agricultural equipment's tires ride within the furrows. When broccoli is being planted, up to four rows of plants can be deployed between the tires of agricultural implements so long as there is adequate clearance under the vehicle, such as a trailer. Each broccoli plant can extend typically eighteen to twenty-two inches above the top of the ridge. The ridge adds six inches to eight inches above the base of the furrow. Thus, a clearance of perhaps thirty inches is required to allow a trailer to pass through the field without damaging the broccoli. It should be emphasized that vast areas of certain Western States are devoted substantially to mono-culture of specialized products such as broccoli and therefore can benefit from specialized equipment. It should also be noted that broccoli is one crop for which multiple harvests can be possible from a single planting provided that the broccoli is not damaged during earlier harvesting processes.
One form of damage that is extremely common occurs when the wheel support structure on trailers which transport the broccoli from the field contacts the outer two rows of a four row set that passes under the vehicle. The maximum dimension of most trailers is dictated primarily by the maximum width and height permitted on public roads. As a result, the most common tire diameter for a trailer in this environment is approximately forty inches. Because the broccoli plant can extend twenty-eight to thirty-two inches from the bottom of the furrow, the two outboard rows of broccoli in the four row set which passes under the trailer are most susceptible to damage by the trailer's undercarriage, hanger bolts, wheel supports, suspension members, etc. during the first harvests. The most common damage resulting from structure contacting the broccoli is to knock it down thereby diminishing subsequent yield appreciably.
Thus, a tension exists between providing a vehicle trailer which is stable on public highways and is dimensioned to operate safely and reliable at highway speeds, while at the same time provides clearance when used in its intended loading environment.
The following prior art reflects the state of the art of which applicant is aware in so far as these prior art teachings appear germane to the process at hand. It is stipulated, however, that none of the structure associated with the known prior art teach singly nor render obvious the instant invention as set forth herein and as particularly claimed.